This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2000-250542, filed Aug. 22, 2000, the entire contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a method for delivering a target object to be processed onto a transfer device and to a table mechanism of the target object, particularly, to a delivering method of the target object, which permits smoothly delivering the target object from a table onto a transfer mechanism, and a table mechanism of the target object.
2. Description of the Related Art
The method of manufacturing a semiconductor device comprises various steps starting with the step of forming a film on a target object to be processed, e.g., a semiconductor wafer, and ending in the step of inspecting the semiconductor device produced. In each of these steps, the semiconductor wafer is delivered from the transfer mechanism of the semiconductor wafer onto the table mechanism of the semiconductor wafer. For example, in the inspecting step, a probe apparatus is used for inspecting the electrical characteristics of the IC chip formed on the surface of the semiconductor wafer.
The conventional probe apparatus comprises a transfer mechanism 13 (hereinafter referred to as xe2x80x9cpincettexe2x80x9d) for transferring a wafer W and a table mechanism 15 (hereinafter referred to as xe2x80x9cmain chuckxe2x80x9d) for receiving the wafer W and disposing thereon the received wafer W, as shown in, for example, FIG. 1. The pincette 13 is arranged in a loader chamber 11, and the main chuck 15 is arranged in a prober chamber 12. A probe card 17 is arranged above the main chuck 15 within the prober chamber 11. The electrical characteristics of the integrated circuit formed on the wafer W disposed on the main chuck 15 are inspected by using the probe card 17 and a tester connected to the probe card 17.
As shown in FIG. 6A, the main chuck 15 comprises a table 15D on which the wafer W is disposed and a plurality of lift pins, e.g., three lift pins 20A-20C, vertically moved on the upper surface of the table 15D. When the wafer W is delivered between the pincette 1 and the table 15D, the lift pins 20A-20C project upward from the upper surface of the table 15D so as to receive the wafer W from the pincette 1 transferred from the loader chamber into the prober chamber. When the pincette 1 retreats into the loader chamber, the lift pins 20A-20C also retreat into the table 15D as shown in FIG. 5B so as to allow the wafer W to be disposed on the table 15D. Under this condition, a predetermined processing (inspection) is applied to the wafer W. After completion of the predetermined processing, the lift pins 20A-20C project upward from the table 15D so as to move the wafer W upward away from the table 15D. As shown in FIG. 6C, the pincette 1 proceeds onto the table 15D, and the lift pins 20A-20C retreat into the table 15D, with the result that the wafer W is delivered onto the pincette 1. Upon receipt of the wafer W, the pincette 1 transfers the wafer W into the loader chamber.
In recent years, the diameter of the wafer W has been markedly increased, and the thickness of the wafer W has been markedly decreased. For example, the diameter of the wafer W has been increased from, for example, 200 mm to 300 mm, and the thickness of the wafer W has been decreased from about 500 xcexcm to about 150 to 200 xcexcm. It is possible for the wafer W to be bent as shown in FIG. 6B. FIG. 6C shows the state that the bent wafer W is delivered from the table 15A onto the pincette 1. Under this state, the pincette 1 is prevented from passing through the clearance between the periphery of the bent wafer W and the table 15A, with the result that the pincette 1 is incapable of being moved into the clearance between the wafer W and the table 15A. It follows that the pincette 1 fails to receive the wafer W, resulting in failure to perform a smooth delivery of the wafer W. The present invention is intended to overcome the above-noted problem.
An object of the present invention is to provide a technology for delivering a bent object to be processed from a table onto a transfer mechanism smoothly and without fail.
Another object of the present invention is to provide a probe apparatus for inspecting the electrical characteristics of the integrated circuit formed on a semiconductor wafer, in which a bent semiconductor wafer can be delivered from a table onto a transfer mechanism smoothly and without fail.
According to a first aspect of the present invention, there is provided a method of delivering a target object to be processed onto a transfer mechanism for allowing the transfer mechanism to take the target object from a table, comprising the steps of:
inclining the target object by making one end of the target object disposed on a table and having a predetermined processing applied thereto higher than the other end; and
allowing the transfer mechanism to hold the inclined target object.
In the method of the present invention, it is desirable to allow a part of the target object to rise from the surface of the table so as to provide air between the target object and the table in the step of inclining the target object.
In the method of the present invention, it is desirable for the step of inclining the target object to comprise the sub-steps of:
making one end of the target object higher than the other end so as to allow the target object to have a predetermined inclination; and
moving upward the target object to a predetermined height while maintaining the inclination.
In the method of the present invention, it is desirable for the step of inclining the target object to comprise the sub-steps of:
moving upward the target object to a predetermined height in parallel to the surface of the table; and
making one end of the target object higher than the other end so as to incline the target object.
In the method of the present invention, it is desirable for the target object to be inclined such that the other end of the target object is brought out of contact with the table in the step of inclining the target object.
In the method of the present invention, it is desirable for the target object to be a semiconductor wafer, for the predetermined processing to be an inspection of the electrical characteristics of the integrated circuit formed on the semiconductor wafer, and for the transfer mechanism to be a pincette for transferring the semiconductor wafer.
In the method of the present invention, it is desirable for the step of inclining the target object of the semiconductor wafer to be performed by controlling the height to which each of a plurality of lift pins for supporting the semiconductor wafer, which are arranged in an upper portion of the table, is moved.
In the method of the present invention, it is desirable for the step of inclining the target object to comprise the sub-steps of:
moving upward at least one lift pin at a predetermined speed so as to cause a part of the target object to rise from the surface of the table, thereby introducing air into the clearance between the target object and the table; and
moving upward each of the lift pins at a speed higher than the predetermined speed so as to move upward the target object.
According to a second aspect of the present invention, there is provided a table mechanism, comprising a table for performing the delivery of the target object to and from a transfer mechanism of the target object, and a plurality of lift pins for causing the target object on the table to rise from the table surface so as to support the target object, wherein at least one lift pin positioned on the side of the transfer mechanism is moved higher than the other lift pins such that the target object is supported by the lift pins in an inclined fashion.
According to a third aspect of the present invention, there is provided a table mechanism for receiving the target object transferred by a transfer mechanism, for applying a predetermined processing to the received target object, and for delivering the processed target object onto the transfer mechanism, comprising:
a table having the target object disposed thereon and provided with a plurality of lift pins in an upper portion thereof, the lift pins being moved upward from within the table onto the outside of the table when receiving the target object transferred by the transfer mechanism and when delivering the processed target object onto the transfer mechanism;
a driving mechanism for vertically moving the plural lift pins; and
a control mechanism for controlling the driving mechanism, the control mechanism moving upward at least one of the lift pins to a position higher than the positions to which the other lift pins are moved upward, when the processed target object is delivered from the table onto the transfer mechanism, so as to incline the target object supported by the plural lift pins.
In the table mechanism according to the third aspect of the present invention, it is desirable for the control of the driving mechanism performed by the control mechanism of the table mechanism to be performed such that, when the processed target object is delivered onto the transfer mechanism, at least one of the lift pins is moved upward at a predetermined speed so as to cause a part of the target object to rise from the surface of the table, thereby introducing air into the clearance between the target object and the table, followed by moving upward the plural lift pins at a speed higher than the predetermined speed.
In the table mechanism according to the third aspect of the present invention, it is desirable for the control of the driving mechanism performed by the control mechanism of the table mechanism to be performed such that the target object is moved upward in parallel to the surface of the table to reach a predetermined height, and that one end of the target object is made higher than the other end so as to incline the target object.
In the table mechanism according to the third aspect of the present invention, it is desirable for the control of the driving mechanism performed by the control mechanism of the table mechanism to be performed such that one end of the target object on the side of the driving mechanism is made higher than the other end so as to impart a predetermined inclination to the target object, and that the target object is moved upward to a predetermined height while maintaining the inclined state.
In the table mechanism according to the third aspect of the present invention, it is desirable for the control of the driving mechanism performed by the control mechanism of the table mechanism to be performed such that the target object is inclined by making higher one end of the target object on the side of the driving mechanism, the degree of inclination being controlled such that the other end of the target object is brought out of contact with the table.
In the table mechanism according to the third aspect of the present invention, it is desirable for the target object to be a target object to be inspected, and for the predetermined processing to be the inspection of the electrical characteristics of the target object.
Further, in the table mechanism according to the third aspect of the present invention, it is desirable for the target object in the table mechanism to be a semiconductor wafer, for the predetermined processing to be an inspection of the electrical characteristics of the integrated circuit formed on a semiconductor wafer, and for the transfer mechanism to be a pincette for transferring the semiconductor wafer.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.